无法从 CVMetalTextureGetTexture 函数获取有效的 MTLTexture
Cant get a valid MTLTexture from CVMetalTextureGetTexture function
我是金属新手。
我想从 CVImageBufferRef 制作 MTLTexture。
我正在使用以下代码示例来执行此操作。
guard
let unwrappedImageTexture = imageTexture,
let texture = CVMetalTextureGetTexture(unwrappedImageTexture),
result == kCVReturnSuccess
else {
throw MetalCameraSessionError.failedToCreateTextureFromImage
}
这里,imageTexture:CVMetalTexture。
这是我在 Obj C 中的代码。
CVMetalTextureRef inputTexture;
NSString* key = (NSString*)kCVPixelBufferPixelFormatTypeKey;
NSNumber* value = [NSNumber numberWithUnsignedInt:kCVPixelFormatType_32BGRA];
AVAssetReaderTrackOutput track = [AVAssetReaderTrackOutput assetReaderTrackOutputWithTrack:video
outputSettings:@{
(NSString *)kCVPixelBufferMetalCompatibilityKey: @YES,
key:value
}];
sampleBuffer = [track copyNextSampleBuffer];
CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
size_t width = CVPixelBufferGetWidth(imageBuffer);
size_t height = CVPixelBufferGetHeight(imageBuffer);
if(kCVReturnSuccess != CVMetalTextureCacheCreateTextureFromImage(kCFAllocatorDefault, _context.textureCache , imageBuffer, NULL, MTLPixelFormatBGRA8Unorm, width, height, 0, &inputTexture)){
__VMLog(@"Texture Creation Error");
}
id<MTLTexture> it = CVMetalTextureGetTexture(inputTexture); //Returns nil
我的 MTLTexture 变量总是得到 nil。甚至没有发生纹理创建错误。但未生成 MTLTexture。
我找到了解决办法。好像它需要一个 id 数组来获取 MTLTexture。
//Wrong approach
id<MTLTexture> it = CVMetalTextureGetTexture(inputTexture);
//Right approach
id<MTLTexture> it[1];
it[0] = CVMetalTextureGetTexture(inputTexture);
我是金属新手。 我想从 CVImageBufferRef 制作 MTLTexture。 我正在使用以下代码示例来执行此操作。
guard
let unwrappedImageTexture = imageTexture,
let texture = CVMetalTextureGetTexture(unwrappedImageTexture),
result == kCVReturnSuccess
else {
throw MetalCameraSessionError.failedToCreateTextureFromImage
}
这里,imageTexture:CVMetalTexture。 这是我在 Obj C 中的代码。
CVMetalTextureRef inputTexture;
NSString* key = (NSString*)kCVPixelBufferPixelFormatTypeKey;
NSNumber* value = [NSNumber numberWithUnsignedInt:kCVPixelFormatType_32BGRA];
AVAssetReaderTrackOutput track = [AVAssetReaderTrackOutput assetReaderTrackOutputWithTrack:video
outputSettings:@{
(NSString *)kCVPixelBufferMetalCompatibilityKey: @YES,
key:value
}];
sampleBuffer = [track copyNextSampleBuffer];
CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
size_t width = CVPixelBufferGetWidth(imageBuffer);
size_t height = CVPixelBufferGetHeight(imageBuffer);
if(kCVReturnSuccess != CVMetalTextureCacheCreateTextureFromImage(kCFAllocatorDefault, _context.textureCache , imageBuffer, NULL, MTLPixelFormatBGRA8Unorm, width, height, 0, &inputTexture)){
__VMLog(@"Texture Creation Error");
}
id<MTLTexture> it = CVMetalTextureGetTexture(inputTexture); //Returns nil
我的 MTLTexture 变量总是得到 nil。甚至没有发生纹理创建错误。但未生成 MTLTexture。
我找到了解决办法。好像它需要一个 id 数组来获取 MTLTexture。
//Wrong approach
id<MTLTexture> it = CVMetalTextureGetTexture(inputTexture);
//Right approach
id<MTLTexture> it[1];
it[0] = CVMetalTextureGetTexture(inputTexture);